Hiya - I bought a 1 gallon glass crock (cookie jar) by Anchor Hocking. Because of the indented lip around the top I can't fit any dish at all in there to hold the veg down. Somewhere on the web I read that you can use a wooden disk - or two semi-circles - for that but to use birch or beech.

So my DH made me two semi-circles out of birch or beech and it worked ok the first time, but now when I use them my kraut goes bad fast. When I use a plastic bag filled with water my kraut is fine, but I don't want to use plastic on my food.

Does anyone how how I could treat these wooden semi-circles so they stop ruining my kraut?

I sometimes use the same system. I don't know if this will help, but I soaked my boards in a heavy brine for a day prior to their first use. I may have even boiled them in the brine, but I can't recall for sure.